If you check out today’s boston.com they talk about D&D and how the D&D community is still going strong. In fact, a lot of people are playing past college AND are using the internet to find new people to play. They also talk about the nerdy stereotype that pushes people to keep their D&D playing a secret while trying to discredit that stereotype.
There is also a question here about nerd and geek culture going mainstream. Video games, once relegated to the few have become more popular as time goes on. The article mentions that Vin Diesel is a D&D player, Curt Schilling (former Boston Red Sox) is an avid Everquest player, and I am sure there is countless other people I am forgetting who like WoW or something nerdy. It seems as time is going on, things considered nerdy become less nerdy and more accepted by the culture. Who knows, maybe it will swing back at some point but for now nerdy has gone mainstream.